CVE-2025-21311

CRITICAL

Published Jan 14, 2025 Modified Jan 24, 2025 CWE-303

Description

Windows NTLM V1 Elevation of Privilege Vulnerability

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CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-303 CWE-303

Affected Products

Vendor	Product	Versions
microsoft	windows_11_24h2	< 10.0.26100.2894
microsoft	windows_server_2022_23h2	< 10.0.25398.1369
microsoft	windows_server_2025	< 10.0.26100.2894

References

Advisories & Patches

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21311

Frequently Asked Questions

What is CVE-2025-21311? +

Windows NTLM V1 Elevation of Privilege Vulnerability It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2025-21311? +

CVE-2025-21311 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-21311? +

CVE-2025-21311 affects products from microsoft, specifically: windows_11_24h2, windows_server_2022_23h2, windows_server_2025. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21311? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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